STRUCTURE OF THE HUMAN VITREORETINAL BORDER REGION

The morphology of the vitreoretinal border region and possible age-rel ated changes in its thickness and its structural elements have been in vestigated by scanning and transmission electron microscopy. The mater ial comprised both eyes from one human fetus and 15 adults. The age di stribution of the adults was two persons in each decade from the third to the tenth decade. Four regions in each eye were studied. The inner limiting membrane (MLI) of the fetal eyes was very thin, of almost eq ual thickness in the four regions, being thickest in the macular regio n. The MLI followed the contour of the Muller cells. A regional differ ence in thickness of the MLI was found in all adult eyes; it was thick est in the macular region. The outer cellular surface of the MLI was u ndulating, whereas the inner vitreous surface was smooth. No significa nt correlation between age and thickness of the membrane could be demo nstrated in adult eyes. The diameter of the previously described fibri ls close to the MLI varied slightly from approximately 15 to 30 nm. No correlation between age and fibril diameter or fibril diameter and re gion was found. Fibril length varied significantly between the four re gions, the longest being in the ora serrata region, the second longest in the equatorial region, the next in the optic disc region and the s hortest in the macular region.